Scoring apparatus and method



Aug. 29, 1967 w, TAYLOR 3,338,199

SCORING APPARATUS AND METHOD Filed March 17, 1965 2 Sheets-Sheet 1 1 \x Q W flay/4 4 40 Z /4 I fi llfl a; /0

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SCORING APPARATUS AND METHOD Filed March 17, 1965 2 Sheets-Sheet 2 3d a liq- 5.

United States Patent M 3,338,199 SCORING APPARATUS AND METHOD William Edward Taylor, Easton, Md., assignor to American Can Company, New York, N.Y., a corporation of New Jersey Filed Mar. 17, 1965, Ser. No. 440,382 13 Claims. (Cl. 11315) The present invention relates generally to metal containers of the type which are provided with an opening feature in the form of a removable section defined by one or more score lines, and more particularly to a novel method and apparatus for'so forming the score line in such a container as to insure that the torn metal edge which remains on the container after the opening action has been effected is smooth and free of thin, sharp fins or burrs which might tend to cut the consumer.

At the present time, many cans are provided with removable sections which are outlined by one or more score lines that are produced either by scoring rolls or scoring dles. When the cans are formed of tin plate or coated steel, these scoring tools are provided with relatively sharp V-shaped scoring edges. Such sharp edges, however, are subject to rapid wear and provide serious maintenance problems. It has been found possible, especially when the cans are made of a softer metal such as an aluminum alloy, to provide more consistently uniform scores if the scoring tools are formed with cut-ting portions which comprise a pair of spaced, gently converging side edges that are joined by a generally horizontal leading or inner edge of considerable width which is not as susceptible to wear as -a sharp V-shaped edge. Such relatively blunt-edged tools are capable of producing sufficiently sharp scores in the metal without excessive wear.

The score produced by such a relatively wide leading edge is normally defined by a thin bottom wall of uniform thickness and substantial width. Since this wall is of uniform thickness, the tearing action may take place at any point along the width thereof, and thus the specific location of the tearing action is not predictable. Usually, such tearing action occurs at one of the ends of the thin bottom wall defining the score, and frequently it occurs on the side of the score adjacent the removable metal section of the container. As a result, all or a major portion of the thin bottom wall remains on the container after the section is removed therefrom, and, since the wall is much thinner and thus much shar er than the full-thickness metal of the container, it in effect becomes a thin, sharp fin or burr which presents a cutting hazard to the consumer throughout the life of the container.

A solution to this problem is presented in United States application S.N. 332,049, filed Dec. 20, 1963, and issued as United States Letters Patent No. 3,244,315 on April 5, 1966, by William 'E. Taylor. This application teaches the formation of a score line wherein the thin bottom wall, instead of being of uniform cross-sectional thickness, tapers gradually in cross-sectional thickness from a section of greatest thickness to a section of least thickness. Since this latter sec-tion offers the least resistance to tearing, the tearing action is invariably located in it, with the result that the location of the tear is completely predictable. By locating this section of least thickness on the side of the bottom wall which is spaced from the removable section of the container, the tearing action will take place on the side of the score which is in spaced relation to the removable area. Thus, the thin bottom wall fin or burr will remain attached to and be discarded with the removable section after the container has been opened. As a result, the edge of the metal which remains on the container is of maximum thickness and has a greatly reduced cutting potential.

Patented Aug. 29, 1967 The present invention provides a novel method and apparatus for forming such a tapered bottom wall for a score line in a container. In accordance with the invention, a scoring punch is provided with a cutting portion comprising converging side edges which terminate in a generally horizontal, leading or inner edge of considerable width, as hereinbefore described. An anvil plate is disposed beneath the punch and is provided with an inclined portion which is disposed beneath the portion of the container in which the score line defining the rem0v able area is to be formed. When the container is scored by the punch, the score line produced by the wide leading edge of the punch will be defined by a thin bottom wall having a generally horizontal upper surface. This bottom wall will not be of uniform thickness, however, since its lower surface is inclined because of the inclined portion of the anvil on which it is supported during the scoring operation. Thus, the thin bottom wall beneath the score, instead of being of uniform cross-sectional thickness, is gradually tapered, as hereinbefore described. The anvil plate portion disposed beneath the wall is so inclined as to form the wall with a section of least thickness disposed at the end thereof which is spaced from the removable section of the container, thereby insuring that the thin bottom wall fin will remain attached to and be discarded with the removable section after the container has been opened.

The instant apparatus and method are advantageous in that a score with a tapered bottom wall, and thus a predictable tearing action, can be formed in a container with a scoring punch having a relatively blunt, generally horizontal leading or scoring edge, thereby avoiding the necessity of having to provide and maintain an inclined leading edge on the punch by difiicult and involved grinding operations.

An object of the present invention, therefore, is to provide a novel apparatus and method for forming a score line in a container to define a removable area therein, the score line being so formed as to provide a predictable tearing action when the area is removed from the container.

Another object is to provide such an apparatus and method for producing a score line which will leave a clean, smooth edge of maximum thickness on the container when the removable area is torn therefrom.

A further object is to provide such a method and apparatus for producing a score line defined by a thin bottom wall which is tapered gradually in cross-sectional thickness to provide a section of least thickness along which the tearing action is most likely to occur.

Still another object is the provision of a novel apparatus for forming a score line defined by a relatively wide bottom wall which is tapered in cross-sectional thickness, said apparatus comprising a scoring punch having a relatively blunt and flat leading edge which is not subject to rapid wear.

A still further object is to provide such an apparatus comprising a scoring member having a relatively blunt, substantially horizontal cutting edge, and an anvil plate with an inclined surface disposed beneath the cutting edge so that a score line can be formed in a thickness of metal positioned on the anvil which will be defined by a thin bottom wall of tapered cross-sectional thickness to provide a wall section of least thickness along which the tearing action is most likely to occur.

Numerous other objects and advantages of the invention will be. apparent as it is better understood from the following description which, taken in connection with the accompany-ing drawing, discloses a preferred embodiment thereof.

Referring to the drawing:

FIGURE 1 is a plan view of the top end of a container which is an example of an article which can be scored by the apparatus and method of the instant invention;

FIG. 2 is an enlarged fragmentary sectional view of a scoring apparatus constructed in accordance with the principles of the instant invention, showing the apparatus prior to the scoring of the container end;

FIG. 3 is a view similar to FIG. 2, showing the scoring apparatus after the container end is scored;

FIG. 4 is an'enlarged fragmentary sectional view of the outer portion of the container end panel, showing the score formed therein by the apparatus shown in FIGS. 2 and 3;

FIG. .5- is an enlarged fragmentary sectional view taken substantially along line 55 in FIG. 1, showing the position of the tear in the bottom wall of each score when the removable section is torn hom the container end; and

FIG. 6 is a view similar to FIG. 3, showing a modified form of the scoring apparatus of the instant invention; and

FIGS. 7 and 8 are views similar to FIGS. 2 and 3, respectively, showing another modified form of the instant scoring apparatus.

As an example of an article which can be scored by utilizing the method and apparatus of the instant invention, FIG. 1 illustrates a can end It) formed of a suitable tearable metal, such as an aluminum alloy or lightweight tinplate, which is of substantially uniform thickness so that its upper and lower surfaces are generally parallel to each other. The end 10 comprises a substantially flat central panel 12 which merges outwardly into an annular countersink wall 14 and a curled marginal flange 1-6 which is adapted to be secured to a complementary can body (not shown) in a double seam of conventional construction.

A first score line 18 is formed in the central panel 12 and extends completely therearound in closely adjacent relation to the countersink wall 14. A second curved score line 20 extends inwardly from the score line 18 at a point 22 and is directed generally towards the center of the end panel 12. A third score line 24 formed in the end panel 12 begins at a point 26 disposed radially inwardly of the score line 18 extends from the point 26 around the end panel 12 in substantially parallel relation to the first score line 18 and then towards the center of the end panel in substantially parallel relation to the second score line 20. The score line 24 merges with the score line 20 approximately at the center of the central panel in a curved score line 28. The score lines 18, 20, 24 and 28, therefore, define a removable rip strip section 30 in the end panel 12 which extends from the center thereof in a curved path substantially radially outwardly to the periphery of the end panel and substantially completely therearound.

Secured to the removable section 30 at its innermost end adjacent the curved score line 28, is a substantially rigid, generally flat lift tab or opening lever 32. The lever 32 is punched or cut from a strip of fiat metal stock and, to incease its rigidity, there are formed therein a plurality of longitudinally extending reinforcing ribs or embossments 34. The lever 32 is secured at its innermost end to the removable area 30 by a peened-over embossment or rivet 36 which is integral with and drawn from the central panel 12, the rivet 36 extending upwardly through an aperture in the innermost end of the lever 32 and having its upper end peened outwardly to secure the lever in place. The outer or free end 38 of the lever is upturned slightly away from the adjacent panel 12, thereby allowing the fingertip of the consumer to be readily inserted under the free end 38 of the lever for the purpose of tearing the removable section 39 from the end panel to open the container.

As a preferred or exemplary embodiment of the instant invention, there is illustrated in FIG. 2 apparatus for forming the parallel score lines 18, 24 in the central panel 12 of the container end 10. The scoring apparatus comprises a vertically reciprocable scoring punch 40 having depending cutting members or portions 42 and 44 which are complementary in configuration to and form the score lines 18 and 24, respectively. The cutting members 42, 44 have a substantially identical cross-sectional shape, and each comprises substantially straight, downwardly converging side edges 46 and 48 which terminate in a flat, generally horizontal leading edge 50 of considerable width.

During the scoring operation, the container end 10 is supported on an anvil plate 52 which is disposed beneath the punch 40. The anvil plate 52 is provided with a flat, generally horizontally extending central portion 54 which is disposed beneath the cutting member 44 of the punch 40 (see FIG. 2). The central portion 54 merges outwardly with an upwardly and outwardly curved portion 56 which is disposed beneath the cutting member 42 of the punch and which in turn merges outwardly with a second substantially flat portion 58 which is disposed above the central portion 54 of the anvil plate. The container end initially rests on the upper flat portion 58 in spaced relation to the central portion '54 and the curved portion 56 of the anvil plate.

When the punch 40 is moved downwardly to score the container end panel 12, as shown in FIG. 3, it will be seen that the panel 12 is pressed downwardly and deformed into engagement with the flat central portion 54 and the curved portion 56 of the anvil plate. Owing to the curvature of the anvil plate portion 56, it is disposed closer to the junction of the outer side edge 46 and leading edge 50 of the punch cutting member 42 than to the junction between the leading edge 50 and the inner side edge 48 of the member 42. Thus, the score line 18 produced in the central panel 12 of the end 10 by the cutting member 42 is defined by a thin bottom wall 60 of nonuniform cross-sectional thickness. The wall 60 comprises a flat upper surface 62, which is parallel to the leading edge 50 of the cutting member, and an upwardly and outwardly curved lower surface 64 which is formed substantially parallel to the curved portion 56 of the anvil plate 52 (see FIG. 4). This bottom Wall 60, therefore, is tapered to provide a section of least thickness which is disposed at the end thereof that is spaced from the removable section 30 of the container end 10.

Since the section of least thickness of the bottom Wall 60 for the score line 18 is spaced from the removable section 30, and olfers the least resistance to tearing, when the removable section 30 is torn from the central panel 12 (as seen in FIG. 5), the thin wall 60 remains attached to and is discarded with the removable section. The edge 65 of the metal which remains on the container end, therefore, is relatively blunt and is free of any sharp burrs or fins which might tend to cut the consumer. It will be readily seen that, because of the tapered cross-sectional thickness of the bottom score wall 60, the tearing action along the score 18 is invariably located in the wall section of least thickness, with the result that the location of the tear is completely predictable.

This advantageous result is accomplished through the use of the instant apparatus and method, without having to provide the cutting member 42 with a tapered or inclined edge which would be subject to rapid wear and consequent maintenance problems.

As shown in FIGS-2, 3 and 5, if the wall 60 beneath the score 18 were not tapered in cross-sectional thickness, but instead were formed of uniform cross-sectional thickness, as is the thin wall 66 beneath the score 24, the

tearing action through the wall would not be predictable.

, is illustrated in FIG. 5 with respect to the thin wall 66 of uniform thickness disposed beneath the score 24.

While the panel portion 12 on which the wall fin 66 remains is removed with the section 30 from the type of container end shown in FIG. 1, in other types of ends where only the section within the scores is removed, the wall fin 66 remaining on the container would present a definite hazard to the consumer.

FIG. 6 discloses a modified form of the instant apparatus in which the punch 40 is of the same construction as that shown in FIGS. 2 and 3. The anvil plate 52a, however, is modified in that it is provided with an upwardly and outwardly extending, substantially straight portion 56a which is disposed beneath the cutting member 42 of the punch 40. This inclined, straight portion 56a, like the curved plate portion 56 shown in FIG. 2, produces a thin wall 60a beneath the score having a non-uniform or tapered cross-sectional thickness, and thus having a section of least thickness along which the tearing action will most likely occur. In most instances, however, the use of the curved anvil portion 56 is preferred because it is easier to form mechanically.

FIGS. 7 and 8 illustrate another modified form of the apparatus of the instant invention. In this embodiment, the scoring punch 140 is provided with a cutting member 142 which is positioned above the curved corner 13 joining the central panel 12 and the countersink wall 14 of the container end 10. The cutting member 142 comprises an outer, vertically extending side edge 146 disposed adjacent the countersink wall 14 and an inner, tapered side edge 148 which merge downwardly in a fiat, horizontally extending leading edge 150. As shown in FIG. 7, the end panel 12 is initially seated on the central, generally fiat, recessed portion 154 of the anvil plate 152. which comprises an upwardly and outwardly curved portion 156 that is disposed below the corner 13 of the end 10 and the cutting member 142.

When the punch 140 is moved downwardly to bring the cutting member 142 into engagement with the cointainer end corner 13, as shown in FIG. 8, the portion of the corner 13 beneath the cutting member is pressed downwardly and deformed into engagement with the curved anvil plate portion 156 as the score 118 is cut in the container end. Because the curved anvil portion 156 is variably spaced from the flat cutting edge 150 of the cutting member 142, the score 118 is defined by a bottom Wall 160 of non-uniform cross-sectional thickness which has a predictable tearing action, as hereinbefore explained.

It is obvious that the apparatus and method of the instant invention may be utilized to form a score or scores having predictable tearing characteristics, as described above, in any type of an article other than a container end or part. Also, it is within the scope of this invention to provide the anvil plate with any suitable type of supporting surface disposed beneath the scoring member, other than the uniformly curved or inclined surfaces disclosed herein, the only requirement being that the anvil surface be so shaped as to be variably spaced from the cutting or scoring member to produce a section of least thickness in the bottom score wall and thus a predictable location of the line of tear through the wall.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

What is claimed is:

1. Apparatus for forming a score in an article to define a removable or tear-out section therein, said apparatus comprising:

means having a relatively blunt edge for cutting said score in said article, and

means disposed beneath said cutting means for supporting said article during the scoring thereof, said supporting means comprising a portion disposed beneath and in oblique relation to said blunt cutting edge,

whereby when said article is scored by said cutting means, said score is defined by a thin bottom wall disposed on said oblique supporting portion and having a non-uniform cross-sectional thickness to provide a section of least thickness through which the tearing action will occur when said removable section is torn from said article.

2. The apparatus of claim 1 wherein said oblique portion of said supporting means is positioned closest to the side of said blunt cutting edge which is disposed in spaced relation to said removable section when said score is being cut in said article, whereby said score wall section of least thickness will be disposed on the end of said wall in spaced relation to said removable section.

3. Apparatus for forming a score in an article to define a removable section therein, said apparatus comprising:

means comprising a blunt edge for cutting said score in said article, and

means disposed beneath said cutting means for supporting said article during the scoring thereof, said supporting means comprising a portion which is disposed beneath and is variably spaced from said blunt cutting edge,

whereby when said article is scored by said cutting edge, said score is defined by a thin bottom wall disposed on said supporting portion and having a section of least thickness through which the tearing action will occur when said removable section is torn from said article.

4. The apparatus of claim 3 wherein said supporting means portion is positioned closest to the side of said cutting edge which is disposed in spaced relation to said removable section when said score is being cut in said article.

5. Apparatus for forming a score in an article to define a tear-out area therein, said apparatus comprising:

means having a relatively blunt, straight edge for cutting said score in said article, and

means disposed beneath said cutting means for supporting said article during the scoring thereof, said supporting means comprising a curved portion disposed beneath said straight cutting edge,

whereby when said article is scored by said cutting edge, said score is defined by a thin bottom wall disposed on said curved supporting portion and having a non uniform cross-sectional thickness to provide a section of least thickness which has the least resistance to tearing.

6. Apparatus for forming a score in a container end to define a tear-out area therein which may be torn from the end without leaving a sharp edge thereon, said apparatus comprising:

a vertically movable punch having a cutting member comprising downwardly converging side edges and a flat, substantially horizontal leading edge, and

an anvil plate disposed beneath said punch for supporting said container end during the scoring thereof, said plate comprising an upwardly and outwardly inclined portion which is positioned beneath said cutting member,

whereby when said punch cutting member is moved downwardly into engagement with said container end to cut said score therein, said inclined plate portion serves to produce a thin bottom Wall beneath said score having a section of least cross-sectional thickness on the outer end thereof which is spaced from said removable area, thereby insuring that said thin wall will be removed with said area from said container end.

7. The apparatus of claim 6 wherein said inclined anvil plate portion is defined by a curved line.

7 81 The apparatus of claim 6 wherein said inclined anvil plate portion is defined by a straight line.

9. A method of forming a score in an article to define a removable area therein, comprising the steps of:

cutting a score in said article with a cutting member having a blunt edge, and

simultaneously supporting the portion of said article to be scored on a surface which is variably spaced from said blunt cutting edge to produce in said article a thin wall of non-uniform cross-sectional thickness which is disposed beneath said score.

10. The method of claim 9 wherein said supporting surface is inclined with respect to said blunt cutting edge to produce a section of least thickness at the end of said Wall which is spaced from said removable area.

11. A method of forming a score in an article to define a removable area therein, comprising the steps of:

cutting a score in said article with a cutting member having a substantially straight, blunt edge, and simultaneously supporting the portion of said article to be scored on a curved surface to produce in said article a thin wall of non-uniform cross-sectional thickness which is disposed beneath said score.

12. The method of claim 11 wherein said supporting surface is so curved as to produce a section of least '5 end Without leaving a sharp edge thereon, comprising the steps of:

cutting a score in said end with a vertically movable punch comprising a cutting member having a substantially straight, horizontal edge, and

10 simultaneously supporting the portion of said end'to be scored on an anvil plate surface which is inclined with respect to said horizontal cutting edge to produce in said container end a thin tapered wall disposed beneath said score and having a section of least thick- 15 ness at one end thereof along which the tearing action will occur.

References Cited UNITED STATES PATENTS 0 804,845 11/1905 Hodgson, 113- 1s 826,601 7/1906 Page 113 1s 2,187,433 1/1940 Punte "113-15 CHARLES W. LANHAM, Primary Examiner.

25 R. D. GREFE, Assistant Examiner. 

1. APPARATUS FOR FOMING A SCORE IN AN ARTICLE TO DEFINE A REMOVABLE OR TEAR-OUT SECTION THEREIN, SAID APPARATUS COMPRISING: MEANS HAVING A RELATIVELY BLUNT EDGE FOR CUTTING SAID SCORE IN SAID ARTICLE, AND MEANS DISPOSED BENEATH SAID CUTTING MEANS FOR SUPPORTING SAID ARTICLE DURING THE SCORING THEREOF, SAID SUPPORTING MEANS COMPRISING A PORTION DISPOSED BENEATH AND IN OBLIQUE RELATION TO SAID BLUNT CUTTING EDGE, 